Fuel pumping unit



June 20, 1950 c. H. RYSTROM 2,512,072

FUEL PUMPING uurr Filed Oct; 25, 1944 3 Sheets-Sheet 1 7M me C. H.RYSTROM FUEL PUMPING UNIT June 20, 1950 Filed Oct. 25, 1944 3Sheets-Sheet 2 &

flM m M June 20,1950 c. H. RYSTROM 2,512,072

mar. puunmc uurr File d Oct. 25, 1944 :5 Sheets-Sheet a Patented June20, 1950 UNITED STATES PATENT OFFIE Charles H. Rystrom, Rockford,'Ill. 7Application October 25, 1944, Serial No 560,326

2 Claims. (Cl. 10342) Myinvention relates generally to fuel pumpingunits, particularly those of a type suitable for supplying oil underpressure to oil burners.

Domestic oil burners present somewhat of a service problem, since theyare frequently located substantial distances from a factory or shopwhere they may be serviced, and because it is frequently hazardous topermit the oil burner to remain out of operation for any substantiallength of time due to the possibility of freezing water pipes, materialsin process, to say nothing of the comfort and health of theinhabitantsof the building in which the oil burner is located.

It is thus an object of my invention to provide an improved fuel feedunit for oil burners, which is of extremely simple design and which isconstructed of a small number of parts so arranged that they are readilyaccessible for inspection, service, and adjustment in the field, thusmaking it unnecessary to return the unit to a factory or service stationfor repairs.

A further object is to provide an improved fuel unit in which thecomponent parts and subassemblies are so arranged that damage or troublewith one component or subassembly does not necessitate replacement of amajor portion of the unit.

Another object is to provide an improved construction in which the partor parts which are the cause of the trouble can be repaired or replacedwithout disturbing the setting or adjustment of other parts of the unitwhich are functioning satisfactorily, and in which most of theadjustments and replacements of components or subassemblies may be madewithout disconnecting any of the piping normally connected to the unit.For example, the fuel oil strainer,

the pumping mechanism, or the pressure regulating valve mechanism can beindividually removed, cleaned, adjusted, and replaced withoutdisconnecting the unit from the piping or removing the bolts that holdthe unit on the burner. Similarly, a new pumping mechanism, togetherwith its shaft, housing, and seal, can be mounted on the valve housingwithout in most cases requiring the disconnection of any of the piping.

A further object is to provide an improved fuel pumping unitincorporating a pressure regulating and bypass valve of the plungertype, in which both the plunger and its bushing can be quickly removedwithout disconnecting the unit from the burner, this facility forremoval of the regulating valve being of particular advantage I when thefuel oil pumped by the unit contains impurities and foreign bodies whichtend to cause the valve'to. stick or fail to seat properly.

A further object is to provide an improved fuel pumpingunit having animproved pressure regulating and bypass valve that does not require apress fit' of any of the valve parts, and which does not require holdingmeans of the clamp typefor positioning them in the housing, such holdingand positioning of the pressure regulating and bypass valve beingaccomplished by a combined valve seat and nozzle port providing element.

A further object is to provide an improved fuel pumping unitparticularly adapted for use in conjunction with oil burners, which isextremely simple in construction, reliable in operation, and

'which may be economically manufactured.

Other objects will appear from the following description, referencebeing had to the accompanying drawings, in which:

Fig. 1 is an end elevational view of the pumping unit, with the end capremoved;

Fig. 2 is an end elevational view taken in the direction opposite tothatof Fig. 1;

Fig. 3 is a fragmentary sectional detail, to an enlarger scale, showingthe internal fuel oil high pressure discharge ducts, and taken on theline 3-.-3 of Fig. 1;

Fig. 4 is a longitudinal sectional view taken on the line 4-4 of Fig. 5;

Fig. 5 is a transverse sectional view taken substantially on the line 55of Fig. 4; and

Fig. 6 is 'afragmentary sectional view taken on the line 55 of Fig. 4.

In general, the fuel pumping unit comprises a gear pump assembly Illhaving a shaft seal assembly l2 detachably secured thereto. pumpassembly is detachably secured to a strainer and regulatingvalve'assembly M, the latter havin a pressure regulating valve assemblyIt retained therein by a, detachable combined valve seat-and outlet portl8.

Referring particularly to the gear pump assembly, it comprises a body 20having a bore 22 extending longitudinally therethrough. The bore 22 isprovided with a pair of keyway slots 24 to permit the ready removal of adrive shaft 2%, by providing clearance for the ends of a pin 28extending diametrically through the drive shaft. This pin provides aseparable driving connection between the shaft 26 and a gear 3% whichmeshes with its counterpart 32 to provide the rotating elementsof. asubstantially conventional gear The gear pump. The gear 32 rotatesfreely on a stub shaft 34 pressed into the body 20.

As best shown in Fig. 5, the gears 30 and 32 rotate in a suitablyconformed opening 36 provided in a casing plate 38. A cover plate 40 andthe casing plate 38 are secured to the body by a plurality of cap screws42. A removable screen 44 is provided with a rim 46 which has a slidingfit around the periphery of the casing plate 38. The cover plate 40 isprovided with an oil inlet opening 48, which communicates with theopening 36 at 50, to the left of the gear wheels permit flow of oil tothe uppermost and lowermost portions of the opening 36 to'improve thesmooth running characteristicsof the pumQ- The discharge from the space52 at the oppo- :preierablyma'de of a synthetic composition rubber,forming a valve face'for engagement with a seat I08 constituting part ofthe valve seat member H0. This valve seat member III) has a port I I2leading from the valve seat to a tapped outlet opening II4, to which adischarge pipe is adapted to be secured for conveying the fuel oil underpressure to the burner nozzle.

site side of the gear wheels flows through a high pressure port 54, thelatter communicating by way. of a duct 56, formed in the body 20, and aduct 58, formed in a regulating valve body 60, withan annular groove 62to supply oil under pressure to the regulating valve assemblylt.

The drive shaft 26 is sealedbymeans; oiia sealing ring 64 preferablymade of bronze or similar alloy, the sealing ring being structurallyreinforced by a band 66 of steel or other highv tensile strength metalwhich is pressed over the sealing ring 84. The sealing ring 64 hasanannular projection Bil which cooperatively engages w t ,r e,, e, a a etNit a oy r similar material, which is pressedpvera seal ring I2, ofsteel or similar alloy, clamping a flexible diaphragm I4 between it anda fiangefl't "formed on the ring I2. The diaphragm "Ifm'ay be of anysuitable flexible material, such as clothimpregnated with a plastic 'orsimilar material, which is oil resistant and ma es the clothsufficientlyflexible to permit movement of the'ring l2 "and cause the ring I0'tomaintain sealing engagement with the annular 'prtion B8 ofthe sealingring 64 as the'latterwears. The'ring'IZ is pressed to the left bya'conical compres'sion coil spring I8, which is seated against aclosurecap 82. The'cap 82 clamps the'pe'ripheral edge of thediaphragm I4 to.the end of thebody 2i being secured to the body by a plurality ofcapscrews 84.- I m The relative rotary movement thus takes place betweenthe bronze annular-projection 68 and the ring I0 of Nitralloyorsimilarmaterial, thereby providing an oil tight seal. If for any reason thissealneedsto be, repaired or replaced, it is clear that by removal of thecapscrews 84 any component or subassembly of the sealing means may beremoved for cleaning, refinishing, or replacement. 1

Similarly, if any of the components or subassemblies of the gear pumpare not operating prop,- erly, the gear pump assembly may be removed asa unit by unscrewing cap screws 86 (Fig. oby which the body 20 issecured to the regulating valve body 60. In addition, upon removal of anend cap 68, by unscrewing cap screws'gsu, the strainer 44 may be removedfor cleaning or replacement, whereupon the gear pump may be removedafter unscrewing cap screws "42.

' Within the regulating valve body there is'aj bore 92 having acounterbore 94 at one end there-- of, part of this counterbore formingthe'annu lar passageway 62 previously mentioned. "A regulating valvesleeve 96 has a chamfered shoulder 98 which has a sliding fit in thecounterbo're' 94 and the chamfer surface of the sleeve presses against asealing ring I00 which maybe made'of The valve I04 is urged to the right(Fig. 5) by a compression coil spring H6, one end of which has a springseat H8 frictionally fitted thereto, the spring seat 8 having a conicalpoint -I20 fitting-in 'a-wider angle conical depression I2I formed inthe'inner end wall of the valve I04. The other end of the spring I I6abuts against-an adjusting nut I22 threadedon a rotatable elongatedfillister head stud I24. The stud I24 has a thin nut I26 suitably fixedthereto and is provided-with'a gasket I28, the kerfed head I30 of thescrew I24 being accessible for engagement by ascrew driver through anopening I32 formed in abap1I3B, the latter beingsecured to the body (Whya plurality of cap screws I38.

The nut I22 is held fromrotation by a pair of pins I40 pressed in thecap I36 and projecting freely'through notches formedin the flangedportion'of the nut I22. It will thus be clear that by rotating theadjustingstud'I24 the degree of compression of the spring -I Hi may bevaried so as to determine the pressure requiredto move the valve I04from its seat I08. The valve I04 has an annular' groove I44 which'underall circumstances is in communication with the passageways I02. on'm theannular groove 62 has access to the face of the valve member I06 througha plurality of slots I46 cut in the end face of the sleeve 96. Thus,when the pressure at the outlet of the pump exceeds apredetermineddesirable value, the'valve I04 will move to the left (Fig.4) to permit dischargejof the oil through'thenozzle connected outletport I I2. 'Whenthe pressure becomes materially greater than thepredetermined pressure required for proper discharge of the oil from theburner nozzle, the spring I IE will be further compressedand the annulargroove I44 will form a. path for the flow of oil from the annular groove62 through the ports I02 and the annular groove I44 toapluralityoffsymmetrically arranged ports 148 which are formed in thevalve sleeve 96.

Theoil which thus enters the bore 92 may be returned to the fuel tank,or other source, through a pipe connected to a tapped outlet openingI50, the oil flowing past a plug I52, through a passageway I53.When'desired, the oil discharge into the bore' 92 maybe returned to atapped inlet port I54 through a bypass duct I56, by removal of the plugI52 andinserting a solid plug in the tapped outlet I50. The oil from thetank or other source is supplied to the pump through a conduit connectedto the inlet port 54, which communicates by way of a' passageway I'58'with the screenchamber I60. v

As best shown in Fig; 6, a tapped suction port I62 is pr0vided,-thisport'bei-ng in communication withthe duct I58. The latter port isprovided for the "attachment of-a*vacuum cause when municating via aduct I66 with the annular groove 62, the gauge thus being enabled toindicate the pressure generated by the gear pump, and assuming that oilis being discharged at the burner nozzle, it will also indicateapproximately the pressure at which the oil is being discharged from theport II 2 to the nozzle, making. due allowance for the pressure drop inthe piping leading to the nozzle. 7

From the foregoing it will be clear thatshould the regulating valveoperate improperly -;for any reason whatsoever, the serviceman need.merely remove the cap IIO, whereupon the valve body I04 and all partscarried thereby, as well as the sleeve 95, may readily be removed, sincethese parts have sliding fits relative to one another and the sleeve 96has a sliding fit in the body 60. Upon replacement of the sleeve 96 andvalve I04, the sleeve is tightly sealed by means of the compositionrubber ring I00, when the cap II is secured in place by means of its capscrews III. Suitable gaskets (not shown) may be used wherever necessaryto assure oil tight seals between the Various separable parts.

It will also be understood, from the foregoing description, that theshaft seal may readily be removed and replaced without disturbing thegear pump mechanism or the regulating valve mechanism. Similarly, thegear pump may readily be removed with the shaft seal without disturbingthe regulating valve or the shaft seal. For servicing the gear pump, thecap 88 and strainer 44 may be removed, thereby making cap screws 42accessible and permitting removal of the gear pump. Adjustment of thepressures at which the valve I04 opens to permit discharge of oil to theburner nozzle and the pressure at which the bypass begins to take placeare adjustable without removing any parts of the unit. If the gasket I28for the adjusting screw I24 should leak, or if the valve I04, or anypart carried thereby should need repair or replacement, the cap I36 maybe removed, making all of these parts accessible for removal. When it isnecessary to clean the sleeve 96 or to remove it for any other purpose,the cap screws I I I are removed, whereupon the cap I I0 whichconstitutes the outlet and valve seat, may be pushed to one side, withthe pipe still connected to it, and the sleeve 96, together with thevalve body I04 and parts associated therewith, may be removed. When itis desired to clean the screen 44, it is necessary merely to remove thecap 88.

It will thus appear that each movable component of the unit is readilyaccessible without in any way disturbing other components, and withoutmaking it necessary to disconnect the unit from any of the pipes or fromthe burner. The regulating valve may be utilized as a pressureresponsive bypass from the high pressure side of the pump to the lowpressure side thereof through the duct I50, or the oil which escapespast the pressure regulating valve may flow through the outlet I55 andpipe connected thereto to the source of oil.

Due to the provision of several radial ports I02 and H38, which arepreferably, but not necessarily, equally spaced circumferentially of thevalve sleeve 96, it has been found that the valve member I04 will notvibrate but instead will move smoothly and gradually to the positionrequired for the maintenanceof the propercoperat ing pressure- Thuspulsations in the oil, flowing to -the burner nozzle are avoided. Ifsuch pulsations in the pressure fuelsupplied to the burner nozzle werepresent, they wouldcause unsatisfact rs oper io Qt h burner,

.The unit is thus ofextreme simplicity and ready accessibility ofitscomponents. This ready accessibiltyof the parts of the unit isalsoafactor contributing to low cost of. manufacture of the unitbecause ofthe rapidity with which the various partslmay be assembled. I

Whilel have shown and described particular embodiments of my invention,it. willbe apparent that" numerous variations and modifications thereofmay be made without departing from the-underlying principles of. theinvention. I therefore desire,'-by :the following. claims, to includewithin: the scope of my invention all such variations and modificationsby which substantially the results of my invention may be obtainedthrough the use of substantially the same or equivalent means.

I claim:

1. A pressure regulating device for the fuel supply system of an oilburner comprising a body having a main bore, a counterbore coaxial withthe main bore and providing a shoulder at the junction of the two bores,a freely removable sleeve having a flange engaging the shoulder, theflange having a free sliding fit in the counterbore and the remainingportion of the sleeve having a free sliding fitin the main bore, saidsleeve having a vent port in the wall thereof, a asket between theshoulder and the flange, a seat forming a, discharge port through whichfuel is discharged to the oil burner, a piston valve having a closesliding fit in said sleeve and having a relatively wide annular groovespaced from its ends, means on the closed end of the piston valve toengage the seat at the discharge port, the major portion of the area ofthe closed end of the piston being subjected to the pressure of fuelsupplied to the device when the piston is in position engaging the seatand the entire cross sectional area of the piston being subjected to thepressure of the fuel supplied when the piston is moved away from theseat, a spring compressed to hold-the piston in engagement with the seatas long as the pressure of fuel supplied is less than a predeterminedvalue, a port in the sleeve to conduct fuel supplied to the annulargroove in the piston valve, the vent port in the sleeve being located soas to communicate with the annular groove in the piston valve only whenthe latter has been moved by the pressure of the fuel a predetermineddistance from the seat, and a removable closure secured to the body tohold the sleeve in position, said closure and body having fiat engagingsurfaces whereby said closure may be slid laterally for removal, theremoval of the closure making the sleeve, valve, gasket, and springaccessible for removal without disconnection of any pipes.

2. A pressure regulating valve comprising a body having a bore andhaving a portion of enlarged diameter at one end of the bore to providea shoulder, a ported sleeve having a sliding fit in the bore and havinga flange engageable with the shoulder, a gasket forming a seal betweenthe flange and the shoulder, means for connecting the source of fuelunder pressure to one end of the bore, a cylindrical valve memberslidable in the sleeve and normally having its end face subjected to thepressure 01 the fuel supplied, said valve member having a groovecooperable with the ports in the sleeve, one port in the sleeveaffording a bypass forthe fuel when the pressure thereof exceeds apredetermined maximum value, means providing a valve seat with dischargeport, adjustable resilient means engaging the valve member and forcingit against said seat, and a single removable member holding the sleevevalve member and resilient means in assembled relationship within thebody, said removable member and body having fiat engaging surfaceswhereby said member may be slid sidewise for removal, said valve seatbeing movable with said member, the removal of the removable membermaking the sleeve, valve member, and resilient means readily accessiblefor removal without disconnection of any pipes.

.- CHARLES H. RYSTROM.

' i REFERENCES CITED The following'lre ferences are of record in the meof thispatent:

v UNITED STATES PATENTS Number Name Date 976,917 Richards Nov. 29, 19101,663,647 Brush Mar. 27, 1928 2,157,089 Storch et al. May 2, 19392,159,720 Wahlmark May 23, 1939 2,163,313 I Voit June 30, 1939 2,184,133Wahlmark Dec. 10, 1939 2,212,833 Huber Aug. 27, 1940 2,232,983 7Wahlmark Feb. 25, 1941 2,233,709 Osborne Mar. 4, 1941 2,309,683

Wahlmark Feb. 2, 1943

